For those carpentry challenged hobbyists,
another option I have used is a cement block stand.
They are cheap, and build time is about 1 hour or less. Just make sure the blocks are set with the open sides up and down, stack a column about every 24 inches to the desired height and add a cap of 2 X 8's laid on side around the the top with a sheet of 1/2 inch plywood or fiber board on that. Seal the plywood/fiberboard edges with 2 inch wide packaging tape. The tank will cover most of the board and it will remain dry. For a quick-shelf, add some 1 X 8 boards on top of the first (bottom) couse of blocks, then add more blocks on top of the boards. This block stand will not move or shake; very stable.
For esthetics you can add a laminated facade which wraps around the front and both sides, with cabinet doors for access to the quick-shelf._________________Keepin' marines happy for 25 years

allmost all frames are not very sturdy untill you put your plywood sheets on the outside. That will shore it up and will not let it move side to side or wobble at all. just make sure you use extra studs to hold up the wieght in the tank over such a long span.

I've seen a lot of aquarium stands that I thought were great, but I must say, that is definitely the finest I've seen! It doesn't look overly complicated either. Simple and beautiful!

In reference to FloridBoy's comment for the cinder block stand, I found a rather attractive one if you want to go that route. I'm not one to plug other websites, and I definitely think this is the superior forum, but click the linke below to see a REALLY nice cinder block stand. (I still like ilikelegs' stand better though)

I would second the motion made by Hasi--I'd love to see in more detail how that was done. I'm planning to get a big tank someday and there's no way I'm paying over $1,000 dollars for a stand when obviously one can make absolutely beautiful stands.

Just did some number crunching & came up 0.6mm deflection per 1.2m span 90x45 pine stress grade MGP10 (lowest grade structural pine) but if your spacing between supporst is 1.5m you get 1.5mm deflection, if your spacing between supporst is 0.9myou get 0.2mm deflection.

These cals do not take into account any extra stiffness from top sheeting to your frame.

If it was me I would be shooting for the least amount of deflection as possible.

Well my husband and I loved the stand made by ilikeleggs that we copied it and made a few personal touches. Ours stands 2' 6" tall x 7' wide. Instead of 3 doors we decided to have two doors and three drawers.We are also going to make a matching canopy for it.

I know this is an older post, but thought I'd throw in my two cents. Obviously, a 100 gallon aquarium isn't something you're going to end up moving on a regular basis, but if you ever have to, a stand that breaks down easily is a really good bet. I have a 60 gallon aquarium; my father and I built a stand out of angle iron for it. We welded two large rectangles (approximately 4.5' by 2.5') to act as the front and back, then used four cross-pieces to make the standard box shape. The cross-pieces bolt into place; so far, I've had no problems with this design. The big plus of the entire thing is that it's ridiculously simple to move. If anyone would like pictures, let me know and I can send some along. Take care.